the oil pump can't physically create too much oil pressure, too much oil pressure would come from an issue with boost/ring blowby/backpressure. oil pumps also work based on crankshaft rpm anyway, this is some weird alternative oil loop that reduces oil pressure/drag when the engine doesn't absolutely need all the splash lubrication up top I GUESS?

 

I have not been keeping up with this novel of a thread as much as I used to. As one of the "early adopters" in three of my cars I do still believe in the purpose, have felt (and heard) improvements in the engine. BUT...I just could not get myself to put in a super heavy weight oil. I did switch to Molygen and do not burn as much oil as I used to.

The theory that I saw that added oil pressure causes wear on the chain tensioners? I have one heck of a hard time buying that.

 

Yeah I was going to say, isnt this the guy running 10w-60 with a ton of power in the NJ/NYC area? 12k seems like a lot of miles now at this point. Also any instagram posts with typos should be taken with a grain of salt, in my opinion.

Not defending anyone, but im not freaking out over that single failure. Don't forget that the 4 cyl diesels have a similar oil pump solenoid since about 2010 with an OEM blank plug alternative. Not sure why but there are a lot of taxis and sprinters out there with this blank plug and many, many miles on the clock.

Lets all breathe a little.

 

It is already a "not listed" service item. We can ask the tens of owners who spend around $10 K in repairs (depending on whether both banks or a single bank issues) on top of the timing system, anyway.

The issue is how often? 40K, 75K, 100K?

 

In engineering terms,
When you consistently show the same results. Once you change a variable, and show different result, what would your conclusion be?
Say you consistently build engines to the same spec, the results are predictable, you change one variable, your results also now change. What would your conclusion be?

 

My car has a Stage 1 and I'm driving since 16'000 Km with the unplugged oil solenoid.
7 Liters 5W40 and 1 Liter of 5W50 from Motul. For me it works very good and next step will be 5 Liters 5W40 and 3 Liters of 5W50.
My target is to fill in 50/50 of 5W40 and 5W50. But this will be the max. I'm living in Switzerland and I don't want to go full of 5W50, because of the cold temperatures here.

If this Guy was driving 10W60 and a lot of Power, this could be (maybe) the reason why the damage came so early.

 

@slobo You mind posting details of your stage one pls?

 

If that is for me, the change must be investigated in several ways:
1 - Is the new result reproducible consistently? At least within the statistical variation for the measurement at hand.
2 - Why had we not seen it before? Is there a difference in procedure or assumption between the latest and previous results?
3 - Keep it open until understood.

Any difference is questionable until proven which one is correct.

 

In EU / Switzerland we are testing our cars on the dyno with DIN or EWG Norm / correction. In this case my car made 535 Hp and 808 Nm of torque. I don't know how much these numbers are in US. Because you guys have different HP numbers / messurements. The Software (ECU) was made from 971plus and the TCU is from PTG from US (via remote from Cliff tunedmercedes).

 

@crconsulting, thank you for the vigilance to expose potential risks of the oil solenoid experiment. you are an important voice in this experiment. please continue to challenge the many unsubstantiated statements regarding supposed benefits of unplugging solenoid.

you and, almost everyone here, are far more intelligent on this topic than i can even dream to be and, i regularly review scientific studies. you're right about investigating how changing variables impact outcomes and, i expect that you understand the importance of a control group in any scientific experiment. the control group must possess the same attributes as the experimental group. otherwise, how does one accurately evaluate the impact of an input to the experiment, if the experiment lacks a control that did not receive similar input.

disconnecting oil solenoid may be the sole contributor to a2d's outcome, excessive wear on chain guides. i don't know and, it appears that there maybe other nonstandard variables in a2d's situation that could unknowingly lead to such outcome. bottom line is that we do not have enough information to draw any conclusions about a2d's outcome.

if it was novel for other mb engines to operate without solenoid, i.e., oil pump always on, a2d's outcome may seem noteworthy. what's impact to mb engines that operate with oil pump always on? how do parts in these mb vehicles differ to accommodate oil pump always on? though answers to these questions may still prove meaningless, because they don't apply to m157 engine and, the answers may provide insights.

without a controlled experiment, we'll have to wait for more data from all the vehicles (including mine) participating in this experiment. what patterns will we observe in the coming years? more oil pump failures? excessive atypical wear? more reliable engines? no one knows.

i participate in the experiment because it makes sense to me and, i accept that it will likely result in unexpected and potentially undesirable/desirable outcomes.

again, thank you for offering counterpoints and encouraging potential participants to understand the consequences of the choice to join experiment.

 

Nice one, thanks. (I'm in UK by the way).
Just wondering how far Joe average is taking things with these.

 

Sorry, I try to give everyone a courtesy of replying but swimming against the tide, you tend to miss a few posts. Unfortunately only have time for a few posts a day.
Lets face it, when someone comes here with an issue those guys are the first to respond. Consistently, and like a dog with a bone, will stick by the original poster until the issue is solved. I constantly see their posts come up in the new post area, as people come here searching for help. I have nothing but praise for enthusiast who give their time and resources to help people who come here in search for answers. Nothing here is personal, nor should anyone take it that way.
I totally appreciate your willingness to learn but, and honestly, I'm not trying to pick on you.

Would you think your mechanical aptitude and understanding at this stage are equal to someone who has been trained thru factory training, specialized schooling and many years of experience rebuilding engines, working on vehicles day in day out? Raise your hand and shout out who here has been trained by MB, (or any other manufacturer) has gone to a technical automotive school and works or has worked in the industry? How many engine builders and tuners here? Would we apply the same logic to having a surgical procedure? Or maybe flying a commercial airliner? My point is the people posting here are working on ONE car, THEIR CAR. NOT ONE poster has actually taken their engine apart here. Or does this for a living. Yet were all convinced that this is a nothingburger because of a deluge of endless google searches and youtube videos. Nothing wrong with asking questions, but at some point, we have to take a leap of faith that someone is more technically qualified than we are. It's against our human nature but its a reality.

Without qualifications and experience in the field we're advocating modifications, we have to be very careful not to openly practice engineering quackery here.

Not sure to what you're actually referring to, but guides should last the life of the engine. Folks abuse their cars in so many different ways, the maintenance issues and abuse issues can muddle the design issues.


It's a general logic question for everyone.....

but I suggest you have the list in the wrong order

Because not one person has actually taken their engine apart or even their top end apart for that matter.
You wont see any tensioners/guides unless someone else takes theirs apart, and since everyone here only works on their own car, no one will take it apart. As I keep mentioning, this is to help prevent "bore scoring" yet not ONE borescope pic before and after.

Yes there was.
a2d_perfomance and several German builders have rebuilt and disassembled several engines, once the solenoid was disconnected, results changed in tensioner wear and timing sprocket failures.

Quote:

Originally Posted by 5soko

As a few German engine builders and M157 owners are learning lately, more oil pressure all the time for a system not designed around such, can potentially have bad effects. The intermediate timing sprocket bearing failing and taking the engine out via premature wear from consistent pressure, may be the worst of it. Add on top of the cake, bore scoring is not solved from more oil pressure, i think a few people may have thought to be the case.

Normally in engineering (and just about any other technical industry) the BURDEN OF PROOF lies on the party that is introducing a departure from an engineered and time tested solution This is one of the few instances I've ever seen where the modifications are only supported by very little usable data, with mostly google searches and monetized youtube videos. And any empiric data is seemingly instantly dismissed or questioned.

Well the shots have been fired across the bow, I see nothing but google searches and you tube videos.
Time to step up and show some empiric data on actual engine wear since this "mod" is also to "improve" engine oiling
We already know the camshaft is being advanced thru timing of oil pressure curve. Now we have some wear data points...


This thread will age, don't worry.

Good Luck folks!

 

5w50 the car is running same oil for the past 6-7 years . The problem is you just can’t see it . You’re not mechanically inclined to understand . And I’m just not going to waste any more time trying to save your parts . Do as you wish . But why would I not want this mod to work? Out of everyone in this chat not one person needed that mod to work like I needed it to work . SMH .

that said . I believe it has a place .it works for cooling down faster after a hard run . Track events etc. does anyone even know how scoring on an m157 even starts? If you believe you are saving your cylinders from scoring at idle then you lost before you started. Cylinder scoring takes place as cylinder pressure rises, and the piston swells closing the gap between it and the walls, it also takes place if a rod is bent, Or when you have intake valve deposits due to the nature of GDI that breaks off and gets between the piston and the walls and the hard chunks gets sandwiched between the pistons and the walls causing scoring . Or your oil viscosity is to low or has thinned combined with high intake temperature that’s the m157 is known for. Making it easier for the fuel to wash out the oil that’s on the walls even further adding in scoring . But thinking that scoring during idle because of a pressure differential of 20 psi from high to low is the reason is crazy. But what’s even crazier is no body has any data . Theres no data that unplugging works . Yet you fight so hard for a mod that is all theoretical. Which is fine . That’s how things get discovered .as in this case something was discovered . It’s just not a savior like all assumed .

 

@slobo
I am glad you enjoy your MOD-upgrade journey is going as well as described: nice!


tip top Matterhorn

We like the smooth transitioning as its gently effective at turning around young used engines. This is a extremely safe, in fact I believe the SAFEST approach for powerful TT engines.

Mixing like for like Motul SP is great: absolutely No concern.

You have a great setup that's delivering awesome results: smart!

You likely have noticed how your engine response now stays consistent when hot as it is when cold. That's only the begining of pistons heat getting under control.

With that you're likely getting increasingly less engine vibrations from 2 to 4kRPM under load, right?
Power is more linearly smooth & STRONG.
Zero waiting sponginess in precise throttle.
That's what this MOD is all about...
(It's nothing about lube, all good already)

The rational is a non-racing everyday engine better run well at 4kR before it gets bumped safely to more extreme output loads.
If engine is unbalanced at 4kR, at 6kR makes greater power from the most active cylinders.


I endorse this MOD for my use besides saying "at your own risk" is because everyone engine use is different - High engine Rpm/output is not casual for engine wear "moded" or not, new or old.

Rod bearings accumulate wear (UOA!) until pistons are loosely mis-guided.
I don't see anyone around here doing BEARINGS MAINTENANCE like BMW mechanics do... This should be normal routine work for redliners.


Hell some ppl even run these engines on 10W-30
Others falks run MB stock FS-Euro, PAO Group-IV, W30, W40, W50, W60...
All choices are personal. Even stock oil lube is good....


The truth is whatever engine oil combination is in use yields matching results.
I've simply evidenced these GDI engines timings are super-touchy about intake camshaft positioning based on vanishing oil viscosity.

The stock oil FRICTION-LUBE is effective. However its VISCOSITY de-tunes hydraulic phasers.


> MB IMPROVED DESIGN ...
Newer MB engines now keep VVT gears on full pressure (MOD-1) with oil solenoid only to limit hot piston squirting.
This fact proves my experimental findings that ECU thrives on stable environment.

MOD-X is a requirement to enable stable engine timings.


> MATCHING TRANNY WORK
Slobo, how have you seen your tranny shifts evolve over 16kKm: before/after ?

• The shifting points
• The gear selection
• The shift quality
• The tranny consistency

My 722.9 has trailed the engine throttle improvements. The stock experience stopped very early on.

 

@51north Have you changed out another filter yet? Look the same or has it cleaned up?
Guide material would show up in the filters, so this is a good/easy thing for folks to pay attention to.
Yeah, At least there was no metal…

 

The only problem with overriding low oil pressure is that it can act stupid when cold with very thick oils. The variators will be at higher pressure, but will slip less. The timing belt will suffer more when cold. This is the main problem. Nothing serious if the pressure remains within limits. Measurement tests would have to be done. Oil on the pistons...it helps things but worsens others. Always at low rpm, that's the problem. The reason for the valve is emissions, but installing it allowed the manufacturer to install a narrower chain. What worries the user of this engine? Install a pressure sensor and keep the pressure below 2 bar, change the oil to TES, and increase the viscosity. Even so, it's a personal choice, and both are correct. For example, Mercedes didn't install a pressure regulating valve on diesel OM651s before 2009, and the chains stretched. After 2012, they installed a valve, and the percentage of stretched chains decreased, but the connecting rods seized up. Blessed are the oil pressure sensors the brand never installed.

 

Oil pressure isn't anything that could cause or prevent wear, pressure is pressure. The only reason low oil pressure is bad is because the massive change in oil pressure tells you something is very, very broken down south. If oil is moving its usually fine but in a severe case it wouldn't make it up to the splash lubricated components like the head. Oil pressure isn't an issue in these because theyre priority main lubricated anyway. In LS engines they're priority head oiling and gravity sorta pushes everything down for some reason. Oil DOES cool however which is why you'd want to lubricate your stuff really well even while idling, a lubed engine is a cool engine which is a clean engine since less stuff is burning off inside.

I come from street racing. 5w50 isn't heavy at all compared to what you think heavy oil is. It also dilutes on startup due to your rich startup cycle to heat the car up and operate it at cold temps anyway so its not the melted tar you're visualizing.The engines would run on 10w60 if you asked them. You would suffer diminished performance and efficiency but its a tradeoff for better surface adhesion and oil pressure that come from those oils based on their design not really their viscosity (10w60 is a racing/high performance diesel oil). The base oil on a 5w50 would have more viscosity modifiers which actually break down over the life of the oil reverting it back to sort of a 5w40 oil anyway. You're just making it so the molecules don't excite as much as the oil heats up but the physical oil is pretty much the same cold to cold with an additive. 5w40 is the best for most daily driven cars. 5w50 is barely asking more the extra 10 number isn't that big of a push when its a 5w50. The 10 in a 10w60 is a bigger deal.

Lastly dedicated drag engines run on like 35wt fixed weight oil LOL. A lot of that is due to methanol washing but the cars also sit for a while so the surface adhesion is desirable but they're often built tighter at the mains so they can spin up with less vibration but then more ring gap for boost anyway even though they only run for like 6-8 seconds at at ime.

Variable oil pumps are the enemy these days due to efficiency. They do not exist for performance reasons. I'm not talking about 276/278/157 specifically. They do it on much worse cars than Mercedes. The thing is most fresh oil is so good these arguments are sorta moot. The problems you have are oils at about 50% of its life or more which is when the proof of the pudding comes out. Amsoil being 100% synthetic, or Pennzoil from natural gas break down less, last longer, hold their additives better because they have no/less hydrocarbons that coke up with use and foul your components. Your valvetrain fouling doesn't come from gas not cleaning the valve head. Yes gas is a solvent and can clean up your valves, but plenty of normal port injected valves carbon foul just as poorly. It comes from burnt oil, and the oil that normally seeps through the valve stem under normal conditions which burn off. It's actually burnt stuff, not "dirt"

Anyway if you DONT want to play with 5w50. I have Signature Series in 0w40 you can play with in an approved viscosity for the engines. Link includes my referral number so I get the sale
https://www.amsoil.com/p/amsoil-sign...zf/?zo=7236674

 

"over and out" is not proper radio communications terminology. Only Hollywood says "over and out".

 

Been a while since I've been here and trying to catch up makes my head hurt. But let's go back to some early facts.

1. Whether the solenoid is connected (active) or not, start up oil pressure behaves as if it was deactivated, i.e. full or unrestricted pressure for the given rpm. Only after initial startup does the solenoid activate to restrict oil pressure. Unrestricted pressure (i.e., normal pressure) at low rpm is still below the 2 bar limit that an activated solenoid would cause.
2. If a solenoid failed (or was disconnected), a soft DTC was recorded -- no CEL.
3. Mercedes literature states to ignore DTC P06DA00 unless there was an accompanying CEL (which I assume to me a different DTC).

Personal observations using an oil pressure gauge as instructed in the WIS show a steading increase in oil pressure to approximately 60 psi. (My oil pressure only reached a little more than 50 psi at 4000 rpm. The ECU limits engine speed to approximately 4000 rpm when in Park or Neutral.) We know that the solenoid deactivates at 3500 rpm, resulting in a sudden doubling of oil pressure.

My car is tuned, but I very seldom run it hard, such as when entering a busy highway. I don't race it or chase boy racers in Hyundais. I might exceed 3500 rpm in low gears when accelerating from a stop, but in 5th, 6th, or 7th gear, 3500 rpm would likely get me a speeding ticket, so my engine would never see "normal" pressure at highway speeds.

I go back to when I first disconnected the solenoid on my C350 and immediately noticed a more responsive engine and said so at the time. I also said that the change was not as noticeable on the SL400, probably due to the already increased performance of the turbos.

In the end, it is an individual choice, and just like politics, all the ranting and raving one way or the other isn't going to change someone's already made up mind.

 

p u s s y

 

It’s NOTHING like politics or political discussion.
This is a FACT based discussion..

It is a personal choice in that you are in control of the decisions you make (not others making decisions for you like politics)
Your actions and decisions directly impact the operation of your vehicle.
Your decisions will also impact the next owners of your vehicle.
Solid engineering is 100% repeatable and everything claimed can be either proven or disproven THRU SOLID TESTING.

The low end drivability improvements, as shown come from VVT premature advance. Running tensioners 100% of the time at full pressure creates friction and heat in the polymer material.

Engineers spec’d tensioner polymer material for a set load, heat and friction parameters. We’re changing that design parameter thru this “mod”.
Now tensioners have 100%(increase in load ) 100% of the time. i.e. 100%( increase) duty cycle.
What happens to plastic/polymer material when it gets too hot and never has a chance to cool?
Would it break up and get soft like we see in the a2d post?

I would say it’s more akin to a religion or “cult” than politics: faith based
6-700 hundred posts per certain individuals rehashing the same scripture

In the end everyone IS free to do what they want to do with their car. I’ve always maintained that it is an individual choice and appreciate the enthusiasm and search for answers.

We just need to make sure we’re not advocating engineering quackery as a solution for a problem that doesn’t exist.

 

Thats the thing, we all came into this the same way. In my case I had a couple customer/ friends back in late 2023 ask me about the mod they saw on Facebook.
I told them I’d do some research and that it sounded great if true. Some of that included conversations with a retired MB engineer (engine development department) I had worked with in the past. Along with testing individual components separately.

Nobody wants this to fail, but when you work on a customers car. You have a responsibility financially and ethically, to vet the product or process.

 

That said, if I remember from Chapter 1 (how ever long ago) the "Official Fix" from MB in the instance of a failed solenoid was to leave it alone - as they fail "open". I suppose we could assume (correctly) that they only care about the engine for the term of the factory warranty.

 

Well, what are the facts?

In the absence of solid testing, we must rely on analysis and analogous experience. Is there experience that can be directly linked to some component failure due to higher, yet normal, oil pressure? And why would a brand known for its engineering expertise and over-engineering design go with component materials that fail the worst-case scenario? Remember, DTC P06DA00 does not give any external notification of a problem (on most of our older cars). I guess you could argue that every Schedule A and Schedule B service would reveal the DTC, but recommended service intervals of 10,000 miles or more seems like a long time (distance) to check for a serious condition.

They are not running full pressure 100% of the time unless you are driving at illegal speeds 100% of the time. Highway driving for me at 70-75 mph has the rpm at 2000-2500. So, based my measurements, I'm at 40-45 psi at those engine speeds.

Not true.

Ha! Politics is a religion! And there are cults aplenty.

With a thread this long, there will be repeats for those that might have missed something.

 

I think that has been superseded.
In other words, official factory position is to do the repair. Those are old doc’s googled and regurgitated here….